Serum Levels of Interleukin-1β and Interferon-γ in Hansen's disease

Background: Hansen's disease is a chronic infectious granulomatous disease caused by Mycobacterium leprae. In leprosy the final immune response depends on predominant effector pathway, M. leprae bacilli are presented by antigen presenting cells to CD4+T cells with subsequent release of Interleukin -12 leading to TH1 response. Release of interferon gamma (IF-gamma) promotes further TH1 response development. IF-gamma along with tumor necrosis factor and IL-2 leads to recruitment of monocytes and their transformation into epithelioid cells and granuloma formation. Aims: Our aim of the study was to analyse serum levels of interleukin-1 beta (IL-1 beta) and interferon-gamma in newly diagnosed untreated patients of leprosy and to co-relate their levels with clinico-histopathological profile. Methods: (including settings and design and statistical analysis used). The study was an analytical cross-sectional study. Fifty newly diagnosed leprosy patients were included in the study. They were categorized into paucibacillary (30) and multibacillary (20) groups. Serum cytokines assay for IL-1 beta and IFN-gamma were performed by ELISA and were compared between the two groups. Mean serum cytokine levels of IL-1 beta and IFN-gamma in both paucibacillary and multibacillary groups were calculated. Significance of mean difference between IL-1 beta and IFN-gamma was assessed using Mann Whitney U test between the two groups. Results: Significantly high serum levels of IFN-gamma were seen in paucibacillary group as compared to multibacillary group. Although serum levels of IL-1 beta were raised in multibacillary group compared to paucibacillary group. The mean difference was not statistically significant. Limitations: The limitation of present study is low sample size. Conclusions: Serum interleukin levels (IL-1 beta and IFN-gamma) are different among the paucibacillary and multibacillary cases. The fact is useful not only to understand the disease pathogenesis but also in sub-categorization of Hansen's disease patients.